The present invention relates to a tape cartridge for use as a backup medium for computer data, and more particularly relates to a two-reel-type tape cartridge (DDS series) including a tape supply-side hub and a tape take-up-side hub placed inside a mainframe case.
In the two-reel-type tape cartridge, respective end portions of the magnetic tapes are connected to hubs through leader tapes. In most cases, the magnetic tape and the leader tape are connected via a splicing tape, and the winding leader of the leader tape is fixed by a tape clamp mounted on the peripheral face of the hub. In such conventional tape connection structure, it is inevitable to have slight steps in a mounting portion of the tape clamp and in a bonding portion of the splicing tape. The shapes of these steps are transferred to the magnetic tape and thereby deforms the magnetic tape, which contributes to occurrence of dropout at the time of read/write access to recording signals.
In order to prevent such transfer of shapes to the magnetic tape, it has been proposed to directly connect the winding leader of the magnetic tape or the leader tape to the hub without use of the tape clamp and the splicing tape. For example, in Japanese Patent Publication No 2002-25218 A (particularly seeing paragraph No. 0022 and FIG. 6), a cylinder-shaped buffering portion is formed around the peripheral face of the hub, and a leader tape is bonded to the peripheral face via adhesive agents. In Japanese Patent Publication No. H06-195930 A (particularly seeing paragraph No. 0011 and FIG. 1), a magnetic tape end on which adhesive agents were applied in advance is bonded to the peripheral face of the hub, and further the tape end is bonded to a leader portion of the magnetic tape. In Japanese Patent Publication No. H05-334843 A (particularly seeing paragraph No. 0008 and FIG. 1), the winding leader of a leader tape is directly bonded to the hub.
In Japanese Patent Publications Nos. 2002-25218 A and H05-334843 A, the leader tape is bonded to the hub directly or through a buffering portion, which makes it possible to prevent shapes from being transferred when the tape end is secured with use of a tape clamp. However, it is necessary to connect the leader tape and the magnetic tape through the splicing tape, which makes it impossible to prevent the transfer of shapes caused by a step by a thickness of the splicing tape. Contrary to this, in Japanese Patent Publication No. H06-195930 A, the magnetic tape is directly bonded to the hub, thereby making it possible to avoid an influence by the splicing tape. However, a large tape tension acts on the magnetic tape in the state that the magnetic tape is all fed, which causes a problem with durability in long-term use. In addition, the tape end is bonded and fixed to the leader portion of the magnetic tape, and therefore it is unavoidable for the winding leader to have a step by the thickness of the tape.
While the tape cartridge as the object of the present invention has a signal recording density and a read/write speed (data transfer rate) for recording signals remarkably higher than those of general tape cartridges, enhancement in computer hard disc capacity has been promoting a demand for tape systems offering read/write access to a larger amount of backup data at a higher speed as well as tape cartridges supporting the tape systems. In such high-speed and high-density tape cartridges, a base tape is thinned to enhance a recording capacity, which fosters tendency toward transfer of shapes. Consequently, how to eliminate the dropout associated with the transfer of shapes is an issue to be solved.